US8660819B2 - Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message - Google Patents

Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message Download PDF

Info

Publication number
US8660819B2
US8660819B2 US13/197,535 US201113197535A US8660819B2 US 8660819 B2 US8660819 B2 US 8660819B2 US 201113197535 A US201113197535 A US 201113197535A US 8660819 B2 US8660819 B2 US 8660819B2
Authority
US
United States
Prior art keywords
value
fuel cell
calibration value
providing
wvt
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Fee Related, expires
Application number
US13/197,535
Other languages
English (en)
Other versions
US20130035898A1 (en
Inventor
Todd K. Preston
Sergio E. Garcia
Joe C. MacHuca
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
GM Global Technology Operations LLC
Original Assignee
GM Global Technology Operations LLC
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by GM Global Technology Operations LLC filed Critical GM Global Technology Operations LLC
Priority to US13/197,535 priority Critical patent/US8660819B2/en
Assigned to GM Global Technology Operations LLC reassignment GM Global Technology Operations LLC ASSIGNMENT OF ASSIGNORS INTEREST (SEE DOCUMENT FOR DETAILS). Assignors: MACHUCA, JOE C., PRESTON, TODD K., GARCIA, SERGIO E.
Priority to DE102012105324A priority patent/DE102012105324A1/de
Assigned to WILMINGTON TRUST COMPANY reassignment WILMINGTON TRUST COMPANY SECURITY AGREEMENT Assignors: GM Global Technology Operations LLC
Priority to CN201210274915.2A priority patent/CN102916206B/zh
Publication of US20130035898A1 publication Critical patent/US20130035898A1/en
Application granted granted Critical
Publication of US8660819B2 publication Critical patent/US8660819B2/en
Assigned to GM Global Technology Operations LLC reassignment GM Global Technology Operations LLC RELEASE BY SECURED PARTY (SEE DOCUMENT FOR DETAILS). Assignors: WILMINGTON TRUST COMPANY
Expired - Fee Related legal-status Critical Current
Adjusted expiration legal-status Critical

Links

Images

Classifications

    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04492—Humidity; Ambient humidity; Water content
    • H01M8/04507—Humidity; Ambient humidity; Water content of cathode reactants at the inlet or inside the fuel cell
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04492—Humidity; Ambient humidity; Water content
    • H01M8/04529—Humidity; Ambient humidity; Water content of the electrolyte
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/04—Auxiliary arrangements, e.g. for control of pressure or for circulation of fluids
    • H01M8/04298—Processes for controlling fuel cells or fuel cell systems
    • H01M8/04313—Processes for controlling fuel cells or fuel cell systems characterised by the detection or assessment of variables; characterised by the detection or assessment of failure or abnormal function
    • H01M8/04664—Failure or abnormal function
    • H01M8/04679—Failure or abnormal function of fuel cell stacks
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
    • H01M8/00—Fuel cells; Manufacture thereof
    • H01M8/10—Fuel cells with solid electrolytes
    • H01M2008/1095—Fuel cells with polymeric electrolytes
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
    • Y02E60/30—Hydrogen technology
    • Y02E60/50—Fuel cells

Definitions

  • This invention relates generally to a system and method for determining whether a water vapor transfer (WVT) unit in a fuel cell system is operating properly and, more particularly, to a system and method for determining whether a WVT unit in a fuel cell system has cross-over leaks by comparing an output of a relative humidity (RH) sensor that measures the relative humidity in a cathode input line to a fuel cell stack and an RH value provided by a high frequency resistance (HFR) circuit that determines membrane humidity of the membranes within the fuel cell stack.
  • RH relative humidity
  • HFR high frequency resistance
  • a hydrogen fuel cell is an electro-chemical device that includes an anode and a cathode with an electrolyte there between.
  • the anode receives hydrogen gas and the cathode receives oxygen or air.
  • the hydrogen gas is dissociated at the anode catalyst to generate free protons and electrons.
  • the protons pass through the electrolyte to the cathode.
  • the protons react with the oxygen and the electrons at the cathode catalyst to generate water.
  • the electrons from the anode cannot pass through the electrolyte, and thus are directed through a load to perform work before being sent to the cathode.
  • PEMFC Proton exchange membrane fuel cells
  • the PEMFC generally includes a solid polymer electrolyte proton conducting membrane, such as a perfluorosulfonic acid membrane.
  • the anode and cathode typically, but not always, include finely divided catalytic particles, usually a highly active catalyst such as platinum (Pt) that is typically supported on carbon particles and mixed with an ionomer.
  • Pt platinum
  • the catalytic mixture is deposited on opposing sides of the membrane.
  • the combination of the anode catalytic mixture, the cathode catalytic mixture and the membrane define a membrane electrode assembly (MEA).
  • MEAs are relatively expensive to manufacture and require certain conditions for effective operation.
  • a typical fuel cell stack for a vehicle may have two hundred or more stacked fuel cells.
  • the fuel cell stack receives a cathode input gas, typically a flow of air forced through the stack by a compressor. Not all of the oxygen is consumed by the stack and some of the air is output as a cathode exhaust gas that may include water as a stack by-product.
  • the fuel cell stack also receives an anode hydrogen input gas that flows into the anode side of the stack.
  • a fuel cell stack includes a series of bipolar plates positioned between the several MEAs in the stack, where the bipolar plates and the MEAs are positioned between two end plates.
  • the bipolar plates include an anode side and a cathode side for adjacent fuel cells in the stack.
  • Anode gas flow fields are provided on the anode side of the bipolar plates that allow the anode reactant gas to flow to the respective MEA.
  • Cathode gas flow fields are provided on the cathode side of the bipolar plates that allow the cathode reactant gas to flow to the respective MEA.
  • One end plate includes anode gas flow channels, and the other end plate includes cathode gas flow channels.
  • the bipolar plates and end plates are made of a conductive material, such as stainless steel or a conductive composite. The end plates conduct the electricity generated by the fuel cells out of the stack.
  • the bipolar plates also include flow channels through which a cooling fluid flows.
  • the membrane within a fuel cell needs to have sufficient water content so that the ionic resistance across the membrane is low enough to effectively conduct protons.
  • Membrane humidification may come from the stack water by-product or external humidification.
  • the flow of reactants through the flow channels of the stack has a drying effect on the cell membranes, most noticeably at an inlet of the reactant flow.
  • the accumulation of water droplets within the flow channels could prevent reactants from flowing therethrough, and may cause the cell to fail because of low reactant gas flow, thus affecting stack stability.
  • the accumulation of water in the reactant gas flow channels, as well as within the gas diffusion layer (GDL), is particularly troublesome at low stack output loads.
  • the cathode exhaust gas from the stack will typically include significant water vapor and liquid water.
  • WVT water vapor transfer
  • WVT water vapor transfer
  • Water in the cathode exhaust gas at one side of the water transfer elements within the WVT unit, such as membranes, is absorbed by the water transfer elements and transferred to the cathode air stream at the other side of the water transfer elements.
  • HFR humidification measuring A technique for determining membrane humidification is known in the art as high frequency resistance (HFR) humidification measuring.
  • HFR humidification measurements are generated by providing a high frequency component or signal on the electrical load of the stack so that a high frequency ripple is produced on the current output of the stack.
  • the resistance of the high frequency component is then measured by a detector, which is a function of the level of humidification of the membranes in the stack.
  • High frequency resistance is a well-known property of fuel cells, and is closely related to the ohmic resistance, or membrane protonic resistance, of the fuel cell membrane.
  • Ohmic resistance is itself a function of the degree of fuel cell membrane humidification.
  • the degree of humidification of the fuel cell membrane may be determined. This HFR measurement allows for an independent measurement of the fuel cell membrane humidification, which may eliminate the need for RH sensors.
  • a typical WVT unit includes membranes made of a special material where the wet flow on one side of the membrane is transferred through the membrane to humidify the dry flow on the other side of the membrane. Because the material that makes up the membranes is relatively thin and the pressure on the cathode inlet side provided by the compressor is higher than the pressure at the cathode outlet side, WVT units sometimes fail where holes form in the membranes so that the airflow on the input side of the WVT unit flows directly to the output side of the WVT unit without passing through the fuel cell stack. Because there is a loss of airflow into the fuel cell stack, the oxygen that is available in the fuel cell stack to provide the reaction is reduced, which reduces the performance of the stack.
  • a system and method for determining whether there is a cross-over leak, or other failure, in a WVT unit that humidifies the cathode inlet airflow to a fuel cell stack in a fuel cell system.
  • the fuel cell system includes an HFR circuit that determines the humidity level of the membranes in the fuel cell stack and an RH sensor that measures the relative humidity of the airflow to the cathode side of the fuel cell stack. The HFR humidity calculation is compared to RH measurements from the RH sensor, and if the difference between the two RH values is greater than a predetermined calibration value, then the system may determine that the WVT unit is failing and needs to be serviced or replaced.
  • FIG. 1 is a simplified schematic block diagram of a fuel cell system
  • FIG. 2 is a flow chart diagram showing a process for determining a potential failure in the WVT unit based on a comparison between an HFR calculation and RH sensor measurement.
  • FIG. 1 is a schematic block diagram of a fuel cell system 10 including a fuel cell stack 12 .
  • a compressor 14 provides an airflow to the cathode side of the fuel cell stack 12 on a cathode input line 16 through a valve 48 and a water vapor transfer (WVT) unit 34 that humidifies the cathode input air.
  • a cathode exhaust gas is output from the stack 12 on a cathode exhaust gas line 18 that directs the cathode exhaust gas to the WVT unit 34 to provide the humidity to humidify the cathode input air.
  • a by-pass line 36 is provided around the WVT unit 34 to direct some or all of the cathode input airflow around the WVT unit 34 .
  • a by-pass valve 38 is provided in the by-pass line 36 , where the positions of the valve 48 and the by-pass valve 38 are controlled to selectively direct the cathode inlet airflow through or around the WVT unit 34 so that when the airflow through the WVT unit 34 and the by-pass line 36 are mixed, the desired or proper amount of humidification is provide to the cathode input airflow, which changes as the stack current density changes.
  • An RH sensor 42 is provided in the cathode input line 16 to provide an RH measurement of the cathode input airflow after it has been humidified by the WVT unit 34 .
  • the fuel cell system 10 also includes a source 20 of hydrogen fuel or gas, typically a high pressure tank, that provides the hydrogen gas to an injector 22 that injects a controlled amount of the hydrogen gas to the anode side of the fuel cell stack 12 on an anode input line 24 .
  • a source 20 of hydrogen fuel or gas typically a high pressure tank
  • an injector 22 that injects a controlled amount of the hydrogen gas to the anode side of the fuel cell stack 12 on an anode input line 24 .
  • various pressure regulators, control valves, shut-off valves, etc. would be provided to supply the high pressure hydrogen gas from the source 20 at a pressure suitable for the injector 22 .
  • the injector 22 can be any injector suitable for the purposes discussed herein.
  • One example is an injector/ejector as described in U.S. Pat. No. 7,320,840, titled Combination of Injector/Ejector for Fuel Cell Systems, issued Jan. 22, 2008, assigned to the assignee of this application and herein incorporated by reference
  • An anode effluent output gas is output from the anode side of the fuel cell stack 12 on an anode output line 26 , which is provided to a bleed valve 28 .
  • nitrogen cross-over from the cathode side of the fuel cell stack 12 dilutes the hydrogen gas in the anode side of the stack 12 , thereby affecting fuel cell stack performance. Therefore, it is necessary to periodically bleed the anode effluent gas from the anode sub-system to reduce the amount of nitrogen in the anode sub-system.
  • the bleed valve 28 When the system 10 is operating in a normal non-bleed mode, the bleed valve 28 is in a position where the anode effluent gas is provided to a recirculation line 30 that recirculates the anode gas to the injector 22 to operate it as an ejector and provide recirculated hydrogen gas back to the anode input of the stack 12 .
  • the bleed valve 28 When a bleed is commanded to reduce the nitrogen in the anode side of the stack 12 , the bleed valve 28 is positioned to direct the anode effluent to a by-pass line 32 that combines the anode effluent gas with the cathode exhaust gas on the line 18 , where the hydrogen gas is diluted to be suitable for the environment.
  • the system 10 is an anode recirculation system, the present invention will have application for other types of fuel cell systems including anode flow shift-systems, as would be well understood to those skilled in the art.
  • the fuel cell system also includes an HFR circuit 40 that determines stack membrane humidity of the membranes in the stack 12 in a manner that is well understood by those skilled in the art.
  • the HFR circuit 40 determines the high frequency resistance of the fuel cell stack 12 that is then used to determine the humidification of the cell membranes within fuel cell stack 12 .
  • the HFR circuit 40 operates by determining the ohmic resistance, or membrane protonic resistance, of the fuel cell stack 12 .
  • Membrane protonic resistance is a function of membrane humidification of the fuel cell stack 12 .
  • the present invention proposes a system and method for determining whether the WVT unit 34 has a cross-over leak, or other failure, or is beginning to fail.
  • the system 10 includes a processor 44 that determines whether a WVT unit failure may be occurring.
  • the processor 44 receives an RH measurement signal from the RH sensor 42 and an HFR-based relative humidity signal from the circuit 40 that gives a representation of the humidity level of the membranes in the fuel cell stack 12 .
  • the two values are compared in the processor 44 , and if the difference is greater than a predetermined allowable calibration value, then a potential WVT unit failure may be occurring, which can be provided to a warning device 46 , such as a light.
  • the HFR circuit 40 will detect the actual humidity of the membranes irregardless of the whether there is a cross-over leak in the WVT unit 34 so that if there is less flow as a result of the cross-over, the membranes will actually get wetter at the same stack current density.
  • the RH sensor 42 in the cathode input line 16 will provide an HR measurement that is less because there is less humidity in the cathode inlet as a result of the cross-over.
  • FIG. 2 is a flow chart diagram 50 showing a process for determining whether there is a cross-over leak, or some other potential failure, in the WVT unit 34 , where the humidified airflow on the cathode input line 16 is lower than what is expected and/or desired.
  • the process for determining whether there is a cross-over leak, or some other potential failure, in the WVT unit 34 can be performed at any suitable time, such as at system start-up, or as often as deemed appropriate, which may increase as the system ages.
  • the algorithm determines a difference between the RH measurement from the sensor 42 provided at box 54 and the HFR membrane humidity calculation from the circuit 40 provided at box 56 .
  • the difference between these two RH values is provided to a decision diamond 58 that determines whether the difference is greater than a predetermined humidity calibration value provided at box 60 .
  • the humidity calibration value may be different for different fuel cell systems.
  • the humidity calibration value can be determined by any suitable technique, and can be fixed or can vary depending on stack operation conditions. In one non-limiting embodiment, the calibration value is set at 20% of the HFR membrane humidity calculation value.
  • the calibration value can be the same across the entire current density output of the fuel cell stack 12 or can increase as the current density of the fuel cell stack 12 increases, where more humidification may be necessary for a proper operation of the stack 12 .
  • the algorithm terminates at box 62 indicating that there is not a problem with WVT unit 34 . If the difference between the RH values is greater than the calibration value at the decision diamond 58 , then the algorithm increases a counter value at box 64 , and then determines whether the counter value is greater than a predetermined count, which may be one or some other suitable value, at decision diamond 66 . If the counter value is not greater than the predetermined count at the decision diamond 66 , then the algorithm does not issue a fault, and terminates at the box 62 .
  • the algorithm sets a diagnostic trouble code (DTC) at box 68 , which can be provided by a trouble light on the dashboard of the vehicle, indicating that the WVT unit 34 may be failing and service should be performed.
  • DTC diagnostic trouble code

Landscapes

  • Life Sciences & Earth Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Manufacturing & Machinery (AREA)
  • Sustainable Development (AREA)
  • Sustainable Energy (AREA)
  • Chemical & Material Sciences (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Electrochemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Fuel Cell (AREA)
US13/197,535 2011-08-03 2011-08-03 Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message Expired - Fee Related US8660819B2 (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US13/197,535 US8660819B2 (en) 2011-08-03 2011-08-03 Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message
DE102012105324A DE102012105324A1 (de) 2011-08-03 2012-06-19 Nutzung von HFR-basierendem Kathodeneinlass-RH-Modell im Vergleich zur Sensorrückkopplung zur Bestimmung einer angefallenen Wasserdampftransfereinheit und Nutzung für einen Diagnosecode und Botschaft
CN201210274915.2A CN102916206B (zh) 2011-08-03 2012-08-03 利用基于hfr阴极进口rh模型与传感器反馈比较确定水蒸汽传递单元故障并且用于诊断代码和信息

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US13/197,535 US8660819B2 (en) 2011-08-03 2011-08-03 Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message

Publications (2)

Publication Number Publication Date
US20130035898A1 US20130035898A1 (en) 2013-02-07
US8660819B2 true US8660819B2 (en) 2014-02-25

Family

ID=47554264

Family Applications (1)

Application Number Title Priority Date Filing Date
US13/197,535 Expired - Fee Related US8660819B2 (en) 2011-08-03 2011-08-03 Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message

Country Status (3)

Country Link
US (1) US8660819B2 (zh)
CN (1) CN102916206B (zh)
DE (1) DE102012105324A1 (zh)

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2014033790A1 (ja) * 2012-08-31 2014-03-06 トヨタ自動車株式会社 燃料電池の制御装置、燃料電池システム、および、燃料電池の制御方法
US9153828B2 (en) 2012-12-28 2015-10-06 GM Global Technology Operations LLC Method to diagnose fuel cell humidification problems
US20140377674A1 (en) * 2013-06-24 2014-12-25 Nuvera Fuel Cells, Inc. Fuel cell air flow method and system
DE102016114738A1 (de) * 2016-08-09 2018-02-15 Audi Ag Verfahren zum Bestimmen eines Leckagestroms und Verfahren zum Betrieb eines Brennstoffzellensystems
DE102017214966A1 (de) * 2017-08-28 2019-02-28 Audi Ag Verfahren zum Betreiben eines Befeuchtungssystems für ein Brennstoffzellensystem sowie Kraftfahrzeug mit einem solchen
DE102017214967A1 (de) * 2017-08-28 2019-02-28 Audi Ag Verfahren zum Bestimmen eines Alterungszustands eines Befeuchters und Brennstoffzellensystem
CN113363540B (zh) * 2021-06-03 2022-12-20 上海重塑能源科技有限公司 增湿器泄漏诊断方法及燃料电池系统

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090075127A1 (en) * 2007-09-17 2009-03-19 Gm Global Technology Operations, Inc. Method for measuring high-frequency resistance of fuel cell in a vehicle
US20110113857A1 (en) 2009-11-19 2011-05-19 Gm Global Technology Operations, Inc. Online estimation of cathode inlet and outlet rh from stack average hfr

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US7320840B2 (en) 2003-07-17 2008-01-22 General Motors Corporation Combination of injector-ejector for fuel cell systems
US7829230B2 (en) * 2007-07-17 2010-11-09 Gm Global Technology Operations, Inc. Method for optimizing diffusion media with spatially varying mass transport resistance
US7687164B2 (en) * 2007-09-21 2010-03-30 Gm Global Technology Operations, Inc. On-line system identification and control of fuel cell humidification via HFR measurements

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20090075127A1 (en) * 2007-09-17 2009-03-19 Gm Global Technology Operations, Inc. Method for measuring high-frequency resistance of fuel cell in a vehicle
US20110113857A1 (en) 2009-11-19 2011-05-19 Gm Global Technology Operations, Inc. Online estimation of cathode inlet and outlet rh from stack average hfr

Also Published As

Publication number Publication date
DE102012105324A1 (de) 2013-02-07
US20130035898A1 (en) 2013-02-07
CN102916206A (zh) 2013-02-06
CN102916206B (zh) 2015-02-25

Similar Documents

Publication Publication Date Title
US9281532B2 (en) Remedial actions for air flow errors in a fuel cell system
US8660819B2 (en) Utilization of HFR-based cathode inlet RH model in comparison to sensor feedback to determine failed water vapor transfer unit and utilize for a diagnostic code and message
CN108288717B (zh) 检测燃料电池气体泄漏的方法
US8450020B2 (en) In-vehicle algorithm for fuel cell stack health quantification
JP4871219B2 (ja) スタック入口のｒｈを増大させるためのシステムレベル調整
US8673515B2 (en) Diagnosis and remediation of low anode hydrogen partial pressure in a PEM fuel cell system
US9306230B2 (en) Online estimation of cathode inlet and outlet RH from stack average HFR
US8623564B2 (en) Method for remedial action in the event of the failure of the primary air flow measurement device in a fuel cell system
US9099701B2 (en) Vehicle application for air storage cathode carbon loss estimation
US9985303B2 (en) Validation and correction of gen 2 anode H2 concentration estimation
US20120040264A1 (en) Hydrogen concentration sensor utilizing cell voltage resulting from hydrogen partial pressure difference
US8679691B2 (en) Injector opening delay diagnostic strategy
US9099703B2 (en) Fast MEA break-in and voltage recovery
US20070281193A1 (en) Multiple pressure regime control to minimize RH excursions during transients
US10329150B2 (en) Fuel cell system and method for determining purity level of hydrogen gas provided to an anode side of the fuel cell
US8231989B2 (en) Method for improving FCS reliability after end cell heater failure
US8524408B2 (en) Stack operation method aimed at cell reversal prevention
US9379396B2 (en) Controls giving −25° C. freeze start capability to a fuel cell system
US20100112385A1 (en) Method for remedial action in the event of the failure of the compressor bypass valve in a fuel cell system
US9853312B2 (en) Method for determining membrane protonic resistance of a fuel cell stack
US20170324101A1 (en) Proactive anode flooding remediation
US9153828B2 (en) Method to diagnose fuel cell humidification problems
US20130209906A1 (en) Reactant control method for a fuel cell system in idle-stop mode
US20110318663A1 (en) Stack cathode inlet rh (relative humidity) control without rh sensing device feedback
US8192878B2 (en) Method and algorithm to detect frozen anode pressure sensor

Legal Events

Date Code Title Description
AS Assignment

Owner name: GM GLOBAL TECHNOLOGY OPERATIONS LLC, MICHIGAN

Free format text: ASSIGNMENT OF ASSIGNORS INTEREST;ASSIGNORS:PRESTON, TODD K.;GARCIA, SERGIO E.;MACHUCA, JOE C.;SIGNING DATES FROM 20110728 TO 20110801;REEL/FRAME:026866/0083

AS Assignment

Owner name: WILMINGTON TRUST COMPANY, DELAWARE

Free format text: SECURITY AGREEMENT;ASSIGNOR:GM GLOBAL TECHNOLOGY OPERATIONS LLC;REEL/FRAME:028466/0870

Effective date: 20101027

FEPP Fee payment procedure

Free format text: PAYOR NUMBER ASSIGNED (ORIGINAL EVENT CODE: ASPN); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STCF Information on status: patent grant

Free format text: PATENTED CASE

AS Assignment

Owner name: GM GLOBAL TECHNOLOGY OPERATIONS LLC, MICHIGAN

Free format text: RELEASE BY SECURED PARTY;ASSIGNOR:WILMINGTON TRUST COMPANY;REEL/FRAME:034186/0776

Effective date: 20141017

FPAY Fee payment

Year of fee payment: 4

FEPP Fee payment procedure

Free format text: MAINTENANCE FEE REMINDER MAILED (ORIGINAL EVENT CODE: REM.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

LAPS Lapse for failure to pay maintenance fees

Free format text: PATENT EXPIRED FOR FAILURE TO PAY MAINTENANCE FEES (ORIGINAL EVENT CODE: EXP.); ENTITY STATUS OF PATENT OWNER: LARGE ENTITY

STCH Information on status: patent discontinuation

Free format text: PATENT EXPIRED DUE TO NONPAYMENT OF MAINTENANCE FEES UNDER 37 CFR 1.362

FP Lapsed due to failure to pay maintenance fee

Effective date: 20220225